Backscattering properties of quasi-horizontally oriented ice crystals for scanning lidars with small tilt angles

Quasi-horizontal orientations of ice crystals were conventionally described using a Gaussian distribution. However, recent research has shown that the exponential distribution provides a more accurate representation of them. The backscattering properties of plate-like and column-like ice crystals with the exponential distribution for lidar with tilt angles ranging from 0° to 15° off-zenith are investigated for the first time in this study. It reveals that using the realistic distribution law significantly impacts the scanning lidar's retrieval algorithms, especially in the case of plate-like ice crystals. It is found that the color ratio is also sensitive to the plate's flutter, while the linear depolarization ratio is sensitive to the orientation of the columns. These new results are very crucial for adjusting the micro-pulse lidar network (MPLNET) retrieval algorithms.